At the same time, the German army occupied Warsaw during the First World War on August 6, 1915 (Calendar, June 26, 1915). The Bavarian Duke Leopold entered Warsaw on August 6, 1915, the German army destroyed the Russian defense line, seized the internal and external fortresses, and this evening occupied Warsaw. A Russian official announcement said that the troops deployed in Warsaw, the third-largest city of the Russian Empire, the Polish capital, were ordered to withdraw from the Vistula River without being attacked. As a defense strategy, the Russian army blasted all the bridges on the river. The Russian army in the retreat had shipped military equipment and other military supplies out of Warsaw. During the fight for the occupation of Warsaw, the two sides waged a fierce